Vent switch, combustion air, and interlocking replacement air
HMI Hoyme Manufacturing Inc. Special Note: Circuits are colored for clarification only and are not necessarily those found in actual installations. Wires of the Combustion Air Damper, however, are colored as shown.
Diagram #11: Forced Air Furnace having a combustion air supply duct and a replacement air supply duct together with a designated ventilation switch and/or bathroom timer to turn on an exhaust fan INTERLOCKED to a replacement air control damper to prove to be open before exhaust fan runs.
2. Replacement Air Damper with Relay and an End Switch (HAC-0x11- SPC)
3. Ventilation Switch and/or bathroom timer with controlled and regular 120Vac 3-Wire supply to furnace area.
4. Relay Adaptor (ADP-1102-TPX) functions as a control centre.
1. Combustion Air and Replacement air damper open during furnace firing.
2. Ventilation Switch and/or bathroom timer opens the Replacement Air Damper. After Damper proves to be opened (INTERLOCKED), the Ventilation Fan and Furnace Fan will turn on.
3. Optional switch (i.e. toggle switch, timer, de-humidistat) allows full control of Replacement Air Damper to open at any time provided it is the PC type.
N.B. Replacement Air Damper is not affected by the ‘Manual’ setting of the furnace fan.
1222-ld - Printed in Canada
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